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Show 448 ANNELIDES. rally furnished with tentacula or filaments, to which, notwithstanding their fleshy nature, some modern naturalists give the name of antennre; and several genera of the second and third are marked with black and shining points, usually considered as eyes. The organization of their mouth varies greatly. ORDER I. TUBICOL..£( I). Some of the Tubicolre form a calcareous, homogeneous tube, probably the result of transudation, like the shell of the ~ollusca, with which however they have no muscular adhesiOn; others construct one by agglutinating grains of sand, fragments of shells and particles of mud, by means of a membrane, also unquestionably transuded; the tube of others again is entirely membranous or horny. To the first belongs the genus SERPULA, Lin. The calcareous tubes of the Serpul~ twine round and cover stones, shells, and all submarine bodies. The section of these tubes is sometimes round, and sometimes angular, according to the species. The body of the animal is composed of numerous segments; its anterior portion is spread into a disk, armed on each side with seve· ral bundles of coarse hairs, and on each side of its mouth is a tuft of branchi~, shaped like a fan, and usually ti~ged with bright colours. At the base of each tuft is a fleshy filament, one of which, either on the right or left, indifferently, is always elongated, and dilated at its extremity into a variously formed disk which serves as (1) M. Savigny adds the .!lrenicolm to this order, and changes its name to S.&n· PULA.CEA; M. Lamarck, adopting his plan, converts the SERPULACEA into S:EDEN· TAniA. The genera of my 'Jlubicolre form the family of the AMPUITRITES, Savigny, and those of the AMPHITRITJEA and SERPULACE..&., Lamarck. They form the order ENTOMozo..&.nJA CnETOl'ODA HETEROClliSINA, Blainvil1e, who, in defiance of his own definition, places there SPxo and PoLYnonus. TUBlCOL.lE, 449 an operculum, and seals up the orifice of the tube when the animal has withdrawn into it( 1 ). Serp. contortuplicata(2), Ell., Corall., XXXVIII, 2. The most common species; its tubes are round. three lines in diameter, and twisted. The operculum is infundibuliform, and the branchi~ are frequently of a beautiful red colour, or variegated with yellow, violet, &c. Vases or other objects thrown into the sea are soon covered by its tubes. Serp. vermir:ularis, Gm.; Mull., Zool. Dan., LXXXVI, 7, 9, &c. A smaller species, with a claviform operculum, armed with two or three small points. The branchi~ are sometimes blue. No spectacle is more beautiful than that of a group of these Serpulre when well expanded. They are found on the coast of France. In others the operculum is flat and bristled with more numerous points(3). One of them is the Serp. gigantea, Pall., Miscel., X, 2, 10. It is always found among the Madrepores, which frequently surround its tube; the branchi~ become spirally convoluted when they enter the latter, and its operculum is armed with two small branching horns, resembling the antlers of a deer( 4 ). M. Lamarck distinguishes the SPIRORBis, Lam., Where the branchial filaments are much less numerous-three or four on each side; the tube is regularly spiral, and the animal usually very small( 5). (1) The disk ofthe common Serpula being funnel-shaped, hasinducednaturalists to consider it as a proboscis, but it is not perforated, and in all the other species it is more or less claviform. (2) It is the same animal as the .!lmphitrite penicillus, Gm., or Proboscidea, llrug., or Probosciplectanos, Fab. Column. Aquat., c, xi, p. 22. (3) They are the G..&.LEOLA.RIJE, Lam. A single operculum is seen, Berl., Schr., IX, iii, 6. (4) The same as the Terebella bicornis, Abildg., Berl. Schr., IX, iii, 4; Seb., III, :tvi, 7, and as the .!lctinia, or Jlnimal:flower, Home, Lect. on Comp. Anatom., II, pl. 1. M. Savigny established his subdivision of the SERPULJE CYMOSPIRJE, of which M. de lllainville has since made a genus, upon this spiral convolution of the branchia:. Add, Te:rebella stellata, Gm., Abildg ., loc. cit. f. 5, remarkable for its opercu· lum, which is composed of three plates stt·ung together. (5) Serpulaspirillum, Pall., Nov. Act. Petrop., V, pl. v, f. 21;-Se:rp. spirorbis, Mull., Zool. Dan. Ill, lxxxvi, 1-6. VoL. II.-3 G |